[opt](packed-file) Avoid unnecessary HEAD Object requests when opening an S3 object

Author: liaoxin01

be/src/io/fs/packed_file_system.cpp

@@ -74,8 +74,7 @@ Status PackedFileSystem::open_file_impl(const Path& file, FileReaderSPtr* reader
         // DCHECK(opts->file_size == -1 || opts->file_size == index.size)
         //         << "file size is not correct, expected: " << index.size
         //         << ", actual: " << opts->file_size;
-        // local_opts.file_size = index.size + index.offset;
-        local_opts.file_size = -1;
+        local_opts.file_size = index.size + index.offset;
         LOG(INFO) << "open packed file: " << index.packed_file_path << ", file: " << file.native()
                   << ", offset: " << index.offset << ", size: " << index.size;
         RETURN_IF_ERROR(